Furnace door frame



May 20, 1958 o. l.. BRAUN FURNACE nooR FRAME 2 Sheets-Sinaai:l l

Filed May 12, 195s VTI mmmwmmmummwd lm -ll I, .7

wmgwd May 20, 1958 o. L. BRAUN FURNACE DOOR FRAME 2 Sheets-Sheet 2 Filed May l2, 1953 ff@ la f3 SL Q United States Patent O 2,835,232 FURNACE Doon FRAME Ottwin L. Braun, Pittsburgh, Pa., assignor to Reliance Steel Products Company, McKeesport, Pa., a corpora tion of Pennsylvania Application May 12, 1953, Serial No. 354,590

3 Claims. (Cl. 122-499) This invention relates to watercooled furnace door frames and, more particularly, to an improved lconstruction which eliminates warping or toe-in of the frame legs upon cooling after removal of the frame for furnace repairs.

Water-cooled furnace door frames for open-hearth furnaces and the like are conventionally fabricated from pressed and welded steel plate and have a water-containing body portion forming the top of the frame and two hollow depending legs opening into the top and forming the sides of the frame. The legs and top of the frame are formed of front and rear plates which are joined together in spaced relation by top and side plates welded to their outer edges. An arch-bar joins the inner edges of the front and rear plates to complete the water-containing enclosure of the frame. The arch-bar defines the opening into the furnace and is continuously and directly exposed to the furnace heat. When the frame is removed to make furnace repairs, the legs frequently warp or toe-in to an extent that their lower ends are not receivable in the recesses provided in the metal foreplate or sill carried by the breast-plate. Before the frame can be re-installed in the furnace, the legs must be straightened and this is a difficult and time-consuming operation which commonly increases the furnace shutdown time.

One of fthe principal objects of this invention is, as

indicated, to provide an improved furnace door frame p construction which will eliminate warping or toe-in of the frame legs upon cooling. To this end, the interior surfaces of the frame legs in the vicinity of the arch-bar are provided with metal heat conductors which are integrally connected by welding with the metal plates forming the frame. In the preferred embodiment of the invention, the heat conducting elements are in the form of pins welded to the internal surface of the arch-bar and to the internal surfaces of the front and back-plates adjacent the arch-bar. The invention also contemplates the use of heat conducting metal platesin place of plural pins. The pins or plates extend into the path of movement of the cooling water flowing through the legs and transfer heatto the water from the arch-bar. In this manner, excessive heating of the arch-bar is prevented, and toe-in of the legs is eliminated upon cooling of the frame after removal from the furnace. The invention thus eliminates the troublesome and costly leg straightening operations heretofore required and reduces the furnace shut-down time when repair is required. v

Other objects and advantages of the invention will become apparent from the following description In the drawings, several embodiments of the invention are shown. In this showing:

Fig. 1 is an elevational view of a water-cooled furnace door frame illustrating a preferred embodiment of the invention;

Fig. 2 is a sectional View taken substantially along the line Il-II of Fig. 1;

Fig. 3 is a top plan view of the frame shown in Fig. 1;

2,835,232 Patented May 20, 1958 Fig. 4 is a sectional view taken along line lV-lV of Fig. l;

Fig. 5 is a fragmentary front elevational view of one leg of a frame illustrating a modified embodiment of the invention;

Fig. 6 is a side view of the leg shown in Fig. 5;

Fig. 7 is a sectional view taken substantially along the line VII- VII of Fig. 5;

Figs. 8, 9 and 10 are views respectively similar to Figs. 5, 6 and 7 illustrating a modified form of the invention; and

Figs. 11, l2 and 13 are views respectively similar to Figs. 5, 6 and 7 illustrating a further modified form of the invention.

In the drawings the numeral 1 designates as a whole a hollow water-cooled frame for a furnace doorway. The top 2 of the frame is a hollow water-containing body portion having legs 3 internally communicating therewith and depending therefrom in laterally-spaced relation and forming the sides` of the frame. Water is supplied to the interior of the frame through a supply conduit 4 to a manifold 5 having nozzles 6 for directing water` into a nose or lintel 7 for protecting the usual skewback channel of the furnace (not shown). The ends of the manifold 5 are connected with vertically-extendin g conduits 8 which supply water to the bottom portions of 'the legs 3. The path of movement of the cooling water through and its exit from the frame 1 is substantially as shown and described in Patent No. 2,427,547 issued September 16, 1947, to W. C. Bulmer and will not be repeated here.

The frame 1 is formed of pressed and welded steel plate in a conventional manner and includes an arch-bar 9. The arch-bar 9 is a flat steel plate shaped to the form of an inverted U having a horizontal portion 10 and depending end portions4 11. The arch-bar 9 defines the opening through the frame 1 into the furnace and has its lateral edges welded to spaced front and back plates 12 and 13 which are of substantially U-shaped configuration. The water-containing enclosure of the frame is completed by a top plate 14, side plates 1S, and bottom plates 16 which are welded to the outer edges of the front and back plates 12 and 13. When mounted in a furnace, the bottoms 16 of the legs 3 are received in recesses in the fore-plate or sill (not shown) mounted on the conventional breast-plate of the furnace.

When the frame is mounted in position in a furnace, the arch-bar 9 is continuously and directly exposed to the heat of the furnace. Upon removal of the frame from the furnace for repairs, the legs cool and their `lower ends generally toe-in or warp inv a direction toward each other to an extent that they cannot be re-inserted in the recesses provided therefor in the furnace supporting sill. Before the frame can be re-installed, it is necessary to straighten the frame legs so that they may be received in the supporting sill recesses of the furnace. This is a troublesome and costly operation and increases the shut-down time of the furnace.

To eliminate warping or toe-in of the legs 3 in this manner, there is provided in accordance with the principles of this invention, heat-conducting means for reducing the working temperature of the arch bar-depending portions 11. As shown in Figs. 1 through 4, this heatconducting means, in the preferred embodiment of the invention, comprises two rows of metal pins 17, preferably steel. The pins 17 are arranged at verticallyu spaced intervals along substantially the entire length of the arch-bar portions 11 and have their ends integrally connected thereto by welding. The pins 17 extend in a horizontal direction into the path of cooling water flowing upwardly through the legs 3 over the internal surface of the arch-bar portions 11 and operate to transfer heat from the arch-bar to the cooling water. The pins being zeeman.

in the path of movement of the cooling water, increase the efficiency of the heat transfer operation by imparting a degree of turbulence to the water iiowing thereover. The arrangement of pins .illnstratedis effective .to reduce the operating temperature of the arch-bar portions 11 and effects an oyerallreductionof theleg temperatures in operation; This has -been foundto eliminate warping and toe-in of the legs upon removal of the frame for furnace` repairs `with va consequent elirn'mation-ofthe troublesome and `costlylstraightening ,operations heretofore required, and a reduction in furnace shut-down timeby reason of such straighteningi operations.

InFigs. through7 lthere is showna modiiiedform of the invention for reducing the working temperaturesk of the-legs `3. Y In ,this showng, theY cooling, pins correspending to the pinsl7 of Figs. lthrough l4 are designated by the numeral 17a. The pins 17a are ofrthesame diameter but have a longery axial length so that they ,project farther into the .path ofmovement of the `water,flowing through the legs. In addition ,to the pins ll7a which are connected directly to lthe ,internal surfaces of the, arch.

or 19 as best shown in.Fig6. The pinsltl `an,dll9f con-` duct heatyaway from `thebackfplates 1?;and 13 and.v effect a reduction` in temperatures of thea'rcl1ban inl the area adjacent the welded connectionoffthe back-` plates-12 and 13 with thel archbar depending vportions 11. The transmission ofheatr away frornthe ar cli -bar connected front and back-plates 12 ,andA 13r inturn veffects a further reduction of the working temperature ofthe arch-bar 11.A

The modification .of the invention illustrated.,inl:igs.

8, 9 and 10: utilizes steel plates 20 as the heat-conductingl medium. The ysteel plates 20 yextendvertically and 'cen-,

trally of the arch-bar depending; portions 11 and have an integral weldedvconnection therewith` The welded connection of each plate 20 extends along the. entire length of the vertical edge thereof abutting against the internal surface of the dependingportions lll.k It, is important that the plate 20 have inintegral lWeldedconnection along its lentire length in order that it willbe effective to transfer heaty in a proper manner since spot welding at spacedintervalsalong its lengthwould not be satisfactory. Accordingly', it will be understood that the plate 20 to be ettectic must not only abut against the internal surface of the arch-barv depending portion 11 along its entire length, but additionally must have an integral welded connection along its entire length.

InFigs. 1l through 13, the reduction ink workingtemperatureis effectedjby steel plates 22 and 23 ,similar to the plate 20 shown in Figs. 8 through 10. The plates 22 and 23 respectively have similar integral weldedconnections along the entire lengthV of. one vertical edge thereof with the front and back-plates l2 and 13. The plates 22and 23 transmit kheat away from the front and back-plates in an area adjacent theiry welded connectionsY with the arch-bar depending vportions 11 in a mannery` similar to the pins 18 and 19 of the modification illustrated in Figs.k 5 through'7.

From the foregoing, it will be apparentthat ,the pins ,17'v or 17a as well as the plate 20, byreasonof their integral heat be transmitted rst into the front and back plates 12'and 13. The cooling action in either case results in lowering the working temperature of the archabar depending portions, and, as a result, warping or toe-in of the legs 3 upon cooling after removal of the frame for furnace repairs is eliminated. Elimination of warping or toe-in of the furnace legs in this manner in turn eliminates the costlyand Atime-,consuming legfstrengthening operations heretofore required in conventional frame constructions.y

While the above specilication and accompanying drawings illustrate and explain several preferred embodiments of the invention,rit ywill be understood that this is. merely by way of illustration, and that various changes may be made therein within-the contemplation of the invention and under the scope of the following claims.

I claim:

l. nadoortframe foran Yopen hearthfurnace having an archbarV of inverted U-shapedefining thefurnace opening, front and, rear platesrespectively extending out-`A wardlyl and upwardly from the, laterally spaced edges of the arch bar and suitable connections between..-said plates providingconnectedhollow water receiving enclosures above, and at ,each side of thearchebar, thecon'ibination 4of water inlets and outlets connected with Vthe water receiving enclosures at each side .of the arch' bar providingfcontinuous circulation ofwater therethrough,

a. plurality tof ,metal heat conducting ,meanssecured to and spaced laterally and vertically ofthe'k inner face Aof kthe legs. of ,f said arch bar, said metal heat conducting means .extending away from said archvbar across the path.

ofvcirculation-of water in said enclosures at each side of the arch .bar irnparting turbulence to the Vwater and substantially uniform cooling ofthe faceof the archbar at the sides .of the door frame opening.

2. The door frarneas defined in claim l wherein the said metal heat conducting means extend to adjacentl the outer and cooler face of the door frame into the cooler portionof the circulating water at the sides of the furnace door frame.

3. In a door Vframe for an open hearth furnace-having` an arch ,bar-.of inverted Ufshaped defining the furnace opening, front and rear plates respectively extending outwardly and upwardly from the laterally spaced Aedges A.of

the arch bar and suitable connections between said platesk providing connected hollow water receiving, enclosures above ,and at each` side of the arch bar, the combination.

of 4water inlets and outlets. connected with the. waterfrer.

ceivingenclosures at each side of the arch bar providing, 'continuous circulation of water therethrough, va plurality of metalY pins projecting inwardly from `each ofthe ,vertically dependingportions of said arch bar andatk vertically f spaced intervals therealong, and a plurality, of metal p ins -projectinginwardly from said front and rear plates at.vertically spaced intervals therealong and at points adjacent. the integral connection of said ,plates with theV depending portions ofy said arch bar.

References Cited in the le of this patent UNITED STATES PATENTS t 

